Before using gmusicbrowser, I was using Clementine, which uses SQLite. I wrote a few queries that would help me create playlists based on length and number of tracks. So I can have a playlist of all albums with 10 or more songs on them, 'EPs' (5-7 tracks), 'Singles' (1-2 tracks), and I also have lists of albums that are over an hour, under 45 minutes, et cetera.

When clementine scans your library, it keeps the track lengths in the db. I assume gmusicbrowser does as well, because it can quickly calculate the total runtime. What do you think about adding 'album length' and 'tracks per album' as filter criteria?

I know sometimes the track number field is written as 4/12, where '12' is the total number of tracks. If this were in use, it would be possible to filter complete/incomplete albums.

Since I posted this, I realized that you can add a filter to the statusbar under your 'Album' tab, and incrementally filter up to albums that have x number if tracks in your library. So this is close to what I was suggesting -- though it would still be good to get this as a rule when creating filters, and it would still be good to be able to use this against total filters, because a 5-track album and a 18-track album might both be full albums.